Japan's Nishikori, 26, struggled with a rib problem before quitting his match against Marin Cilic with the score 6-1 5-1 in the Croat's favour.

Gasquet seemed to hurt his back reaching for a shot at 3-2 down against fellow Frenchman Jo-Wilfried Tsonga.

He called it a day at 4-2 and 40-0 down against the 12th seed.

Wimbledon men's singles quarter-finals

Sam Querrey (USA) [28] v Milos Raonic (Can) [6]

Roger Federer (Swi) [3] v Marin Cilic (Cro) [9]

Jiri Vesely (Cze)/Tomas Berdych (Cze) [10] v Lucas Pouille (Fra) [32]

Jo-Wilfried Tsonga (Fra) [12] v Andy Murray (GB) [2]

Nishikori struggles again

The Japanese player, 26, had problems with his serve and movement against the ninth seed, and twice called for a doctor on court who gave him medication before the match was halted at 6-1 5-1 in Cilic's favour. Nishikori also withdrew from last year's Wimbledon with a calf problem.

"It was too much pain - I could not really compete," he said. "Every point I played it got worse. I did not want to but I had to retire."

The Croat served a total of 17 aces on court nine and broke Nishikori on five occasions.

The pair were playing each other in a Grand Slam for the first time since the 2014 US Open final, which Cilic won.

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Not a fair fight - Nishikori retires against Cilic

Raonic fights back from two sets down

Canadian sixth seed Milos Raonic battled from two sets down for the first time in his career to beat Belgian 11th seed David Goffin 4-6 3-6 6-4 6-4 6-4 on court two.

The 25-year-old, a semi-finalist in 2014, struggled in the opening two sets, winning only 67% of points on his first serve in the second set.

That statistic improved dramatically after the rain break during the third set as Raonic, who rained down 22 aces, booked a last-eight match against American Sam Querrey.

The 28th seed followed up his shock win over Novak Djokovic with a 6-4 7-6 (7-5) 6-4 victory over world number 51 Nicolas Mahut. In doing so, Querrey became the first American man to reach a Grand Slam quarter-final for five years.

Berdych and Vesely embark on an epic

Tenth seed Tomas Berdych and fellow Czech Jiri Vesely must return to court three on Tuesday after their last-16 tie was suspended because of bad light before the start of the fifth set.

Vesely, 22, the world number 64, fought back from two-sets-to-one down to win a mammoth fourth set tie-break 11-9.

The pair will resume at 13:00 BST for a chance to face Lucas Pouille in the quarter-finals.

Pouille, seeded 32, recorded a surprise 6-4 4-6 3-6 6-4 10-8 win over 19th seed Bernard Tomic of Australia, in just under three hours on court 12.

The 22-year-old Frenchman had never won a tour-level match on grass before this year's Wimbledon.

More British doubles success

Jonny Marray, who won the Wimbledon men's doubles title in 2012, is into the fourth round of the competition as he and partner Adil Shamasdin of Canada beat 15th seed Pablo Cuevas and Marcel Granollers 6-3 4-6 6-4 3-6 14-12.

But the match was punctuated with bizarre scenes as Cuevas and Granollers showed their anger at umpire Aurelie Tourte.

Tourte handed the pair a second code violation after Cuevas hit the ball out of the court in frustration at double-faulting. That led to the Uruguayan and his Spanish partner sitting down and refusing to play the final game.

The earlier code violation was handed to Cuevas for unsportsmanlike behaviour after he was refused permission to take a toilet break and threatened to urinate into a ball can.

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